In the obituary of Sir William Rowan Hamilton by Augustus De Morgan published in the Gentleman's Magazine, vol. 1 (1866), Hamilton's date of birth was wrongly given as the 5 August, 1805. This error in the original text has accordingly been corrected. In fact, Hamilton was born at midnight between the 3rd and 4th August of that year (see the Life of Sir William Rowan Hamilton by Robert Percival Graves and William Rowan Hamilton by Thomas L. Hankins). Hamilton's date of birth is given as 4 August, 1805 on his tombstone in Mount Jerome Cemetery, Dublin.
David R. Wilkins